<!DOCTYPE html>
<html>
	<head>
		<meta charset="utf-8">
		<title></title>
		<script src="http://libs.baidu.com/jquery/2.0.0/jquery.min.js"></script>
		<script>
			$(function(){
				$("#username").keyup(function(){
					var username = $(this).val();
					$("#usernameInfo").html("长度"+username.length);
				});
			});
		</script>
	</head>
	<body>
		<form action="register" method="post">
			<table border="0" cellspacing="0" cellpadding="0">
				<tr><th>用户注册</th></tr>
				<tr><td><input type="text" id="username"/><label id="usernameInfo"></label></td></tr>
				<tr><td><input type="text" id="password"/><label id="passwordInfo"></td></tr>
				<tr><td><input type="submit" id="submit"/><label id="submitInfo"></td></tr>
			</table>
		</form>
	</body>
</html>
